diff --git a/src/impls/codec.rs b/src/impls/codec.rs
index b51e6e7..e643703 100644
--- a/src/impls/codec.rs
+++ b/src/impls/codec.rs
@@ -71,7 +71,7 @@ fn consolidate_slice<T: Ord>(slice: &mut [(T, usize)]) -> usize {
 }
 
 /// A region that encodes its data in a codec `C`.
-#[derive(Default, Debug)]
+#[derive(Default, Debug, Clone)]
 pub struct CodecRegion<C: Codec, R = OwnedRegion<u8>> {
     inner: R,
     codec: C,
diff --git a/src/impls/columns.rs b/src/impls/columns.rs
index e745ba9..efcf769 100644
--- a/src/impls/columns.rs
+++ b/src/impls/columns.rs
@@ -48,7 +48,7 @@ use crate::{CopyOnto, OwnedRegion, Region};
 ///     assert!(row.iter().copied().eq(r.index(index).iter()));
 /// }
 /// ```
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 #[cfg_attr(
     feature = "serde",
diff --git a/src/impls/offsets.rs b/src/impls/offsets.rs
index b51c131..8ee853e 100644
--- a/src/impls/offsets.rs
+++ b/src/impls/offsets.rs
@@ -34,7 +34,7 @@ pub trait OffsetContainer<T>: Default + Extend<T> {
 /// A container for offsets that can represent strides of offsets.
 ///
 /// Does not implement `OffsetContainer` because it cannot accept arbitrary pushes.
-#[derive(Debug, Default)]
+#[derive(Eq, PartialEq, Debug, Default, Clone, Copy)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum OffsetStride {
     /// No push has occurred.
@@ -136,7 +136,7 @@ impl OffsetStride {
 }
 
 /// A list of unsigned integers that uses `u32` elements as long as they are small enough, and switches to `u64` once they are not.
-#[derive(Eq, PartialEq, Ord, PartialOrd, Clone, Debug, Default)]
+#[derive(Eq, PartialEq, Clone, Debug, Default)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct OffsetList {
     /// Offsets that fit within a `u32`.
@@ -216,7 +216,7 @@ impl OffsetList {
 
 /// An offset container implementation that first tries to recognize strides, and then spilles into
 /// a regular offset list.
-#[derive(Default, Debug)]
+#[derive(Eq, PartialEq, Default, Debug, Clone)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub struct OffsetOptimized {
     strided: OffsetStride,
diff --git a/src/impls/slice.rs b/src/impls/slice.rs
index 7de69ee..50ed413 100644
--- a/src/impls/slice.rs
+++ b/src/impls/slice.rs
@@ -190,12 +190,18 @@ impl<'a, C: Region, O: OffsetContainer<C::Index>> IntoIterator for ReadSlice<'a,
 }
 
 /// An iterator over the items read from a slice region.
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct ReadSliceIter<'a, C: Region, O: OffsetContainer<C::Index>>(
     &'a SliceRegion<C, O>,
     Range<usize>,
 );
 
+impl<'a, C: Region, O: OffsetContainer<C::Index>> Clone for ReadSliceIter<'a, C, O> {
+    fn clone(&self) -> Self {
+        Self(self.0, self.1.clone())
+    }
+}
+
 impl<'a, C: Region, O: OffsetContainer<C::Index>> Iterator for ReadSliceIter<'a, C, O> {
     type Item = C::ReadItem<'a>;
 
@@ -361,6 +367,23 @@ where
     }
 }
 
+impl<R, O> ReserveItems<SliceRegion<R, O>> for ReadSlice<'_, R, O>
+where
+    for<'a> R::ReadItem<'a>: ReserveItems<R>,
+    R: Region,
+    O: OffsetContainer<R::Index>,
+{
+    fn reserve_items<I>(target: &mut SliceRegion<R, O>, items: I)
+    where
+        I: Iterator<Item = Self> + Clone,
+    {
+        target
+            .slices
+            .reserve(items.clone().map(|read_slice| read_slice.len()).sum());
+        ReserveItems::reserve_items(&mut target.inner, items.flatten());
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/impls/tuple.rs b/src/impls/tuple.rs
index ff62d67..600960c 100644
--- a/src/impls/tuple.rs
+++ b/src/impls/tuple.rs
@@ -109,6 +109,22 @@ macro_rules! tuple_flatcontainer {
                         tuple_flatcontainer!(reserve_items target items $($name)* @ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31);
                 }
             }
+
+            #[allow(non_camel_case_types)]
+            #[allow(non_snake_case)]
+            impl<$($name, [<$name _C>]: Region ),*>
+                ReserveItems<[<Tuple $($name)* Region>]<$([<$name _C>]),*>>
+                for ($($name,)*)
+                where
+                    $($name: ReserveItems<[<$name _C>]>),*
+            {
+                fn reserve_items<It>(target: &mut [<Tuple $($name)* Region>]<$([<$name _C>]),*>, items: It)
+                where
+                    It: Iterator<Item = Self> + Clone
+                {
+                        tuple_flatcontainer!(reserve_items_owned target items $($name)* @ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31);
+                }
+            }
         }
     );
     (reserve_items $target:ident $items:ident $name0:ident $($name:ident)* @ $num0:tt $($num:tt)*) => {
@@ -120,6 +136,15 @@ macro_rules! tuple_flatcontainer {
         }
     };
     (reserve_items $target:ident $items:ident @ $($num:tt)*) => {};
+    (reserve_items_owned $target:ident $items:ident $name0:ident $($name:ident)* @ $num0:tt $($num:tt)*) => {
+        paste! {
+            ReserveItems::reserve_items(&mut $target.[<container $name0>], $items.clone().map(|i| {
+                i.$num0
+            }));
+            tuple_flatcontainer!(reserve_items_owned $target $items $($name)* @ $($num)*);
+        }
+    };
+    (reserve_items_owned $target:ident $items:ident @ $($num:tt)*) => {};
 }
 
 tuple_flatcontainer!(A);
@@ -162,7 +187,7 @@ cfg_if::cfg_if! {
 #[cfg(test)]
 mod tests {
     use crate::impls::tuple::TupleABCRegion;
-    use crate::{CopyOnto, MirrorRegion, Region, StringRegion};
+    use crate::{CopyOnto, FlatStack, MirrorRegion, Region, StringRegion};
 
     #[test]
     fn test_tuple() {
@@ -221,4 +246,12 @@ mod tests {
         assert!(cap > 0);
         assert!(cnt > 0);
     }
+    #[test]
+    fn test_reserve_items() {
+        let mut c = FlatStack::default_impl::<(usize, String, Vec<String>)>();
+        c.copy((1, format!("Hello"), &["abc"]));
+
+        let mut c2 = FlatStack::default_impl::<(usize, String, Vec<String>)>();
+        c2.reserve_items(c.iter());
+    }
 }
diff --git a/src/lib.rs b/src/lib.rs
index 493208a..b84f7fd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -278,6 +278,15 @@ impl<'a, R: Region> Iterator for Iter<'a, R> {
 
 impl<R: Region> ExactSizeIterator for Iter<'_, R> {}
 
+impl<R: Region> Clone for Iter<'_, R> {
+    fn clone(&self) -> Self {
+        Self {
+            inner: self.inner.clone(),
+            region: self.region,
+        }
+    }
+}
+
 impl<R: Region, T: CopyOnto<R>> FromIterator<T> for FlatStack<R> {
     fn from_iter<I: IntoIterator<Item = T>>(iter: I) -> Self {
         let iter = iter.into_iter();
@@ -287,14 +296,12 @@ impl<R: Region, T: CopyOnto<R>> FromIterator<T> for FlatStack<R> {
     }
 }
 
-impl<R: Region> Clone for FlatStack<R>
-where
-    for<'a> R::ReadItem<'a>: CopyOnto<R>,
-{
+impl<R: Region + Clone> Clone for FlatStack<R> {
     fn clone(&self) -> Self {
-        let mut clone = Self::merge_capacity(std::iter::once(self));
-        clone.extend(self.iter());
-        clone
+        Self {
+            region: self.region.clone(),
+            indices: self.indices.clone(),
+        }
     }
 }